Executive Summary

Comparing casual users with members we find a few notable differences.

-todo

Who rides most often?

Overall, members take the majority of rides.

On weekends however casual use doubles and even exceeds member use.

Breaking down the number of rides by month, we can see that while the season is important for all riders, casual users are much less willing to ride in the winter months. From December to February, the system sees very little casual use.

Summarizing the previous three graphs, casual use of the system is much more variable than for members. It is maximized during summer weekends and minimized during winter weekdays.

How do trip distances vary?

This is a bit surprising. For trips that start and end at different stations, the average trip is about the same distance for both classes of users, two and a half kilometers.

Seasonally, average trip distance is smallest during the winter and largest
in summer, but only by about half a kilometer. Trip distance does not change much over the course of the week.

A special case: pleasure cruises?

For the above analysis we removed trips that start and end at the same station since they have an apparent distance of zero. We believe it’s likely that pleasure cruises make up a large portion of these rides. These rides average an hour long for casual users. In the next section on ride duration we’ll see the average of all casual trips is just over 30 minutes, an interesting difference.

Rider Type Possible pleasure cruises Avg trip minutes Percent of trips
casual 315156 61 16.029109
member 110279 26 4.221841

These round-trips represent about 10% of all bike use and about 16% of all casual use. We also see above that casual users outnumber members 3 to 1 in this interesting subset of rides.
We’ll return to these trips in a later section, after we have explored ride duration.

How much time is spent on an average ride?

Casuals ride more than twice as long as members, on average. There isn’t much variation in ride duration over the week other than a slight increase on the weekend.

Seasonally, casual rides have a large amount of variation. The small number of winter trips taken tend to be short - half the length of rides at the peak of summer.

Pleasure cruises?

Earlier we noted the possibility that 10% of all rides (and 16% of casual rides) were round-trip pleasure cruises starting and ending at the same station, likely near the rider’s home. The two graphs below provide more evidence for this idea.

If our hypothesis is correct, the percentage of this type of ride should shrink in winter and grow in summer and be mostly confined to casual users. This first graph shows exactly this pattern.

Second, if our idea is correct we should also see trip duration becoming longer in summer and shorter in winter. This should strongly affect casual users but have little effect on members, who have a 45-minute time limit. This graph demonstrates this pattern as well.

Learning how these rides differ in destination, length, or speed would require some sort of GPS tracking data from the bikes, which is outside the scope of this dataset. For now we note the strong possibility that about ten percent of all trips are taken for enjoyment rather than travel, and that casual users dominate this market segment.

Speed, Time in the Saddle, Comfort

We’ve seen that casuals and members ride about the same distances, but members spend less time on the bikes. The graph below shows that members are about 30% faster on average.

We now know that members ride more often and casuals ride longer: who rides the most total minutes? Casual users do!

Since casual users spend so much more time in the saddle, it might be a worthwhile experiment to trial a set of more comfortable, relaxed-ride bikes aimed at users who want to cruise in comfort. In the maps section below we identify regions of the city where casual users dominate the ridership.

Which stations do casuals use?

We’ll look at this question in two parts. First we’ll examine who uses the most and least popular stations. Second we will plot these stations on a map of Chicago.

Station popularity

we’ll sort the stations by popularity (number of trips that start there) and colour the points by the proportion of the type of user. We can extract three main insights from the graph below:

  1. Overall, most stations are used primarily by members
  2. The least popular stations are dominated by casual use
  3. A few of the city’s most popular stations are over 75% casual use
  4. These might make excellent targets for any pilot programs targeting casual users

Next we’ll map all the bike stations in the system and colour them by the percentage of casual rides that start there.

Next let’s highlight hot spots. Any station with over 70% casual use will be red, and we’ll also give busier stations larger dots.

Finally let’s zoom in on the notable hot spot near Navy Pier. Of all stations with over 70% casual use, these are the busiest.

These stations are all on and around the waterfront between Soldier Field and Navy Pier. They represent what is easily the most popular casual use desination anywhere in the city, demonstrating a consistent pattern of activity by casual users of the system.

Traffic Flow: Hourly and daily patterns

In our last piece of analysis we will examine the overall traffic flow for patterns

We calculate the overall traffic flow in the bike system. Each arrow represents overall motion of all the bikes during a one-hour period. An arrow pointing northwest means that during that hour, bikes tend to be moving in that direction. We’ll use this to examine the difference in overall traffic flow over each hour in a week, comparing members vs casual users.

Technical note: to calculate this metric, each trip is treated as a vector. All vectors in a particular hour are added end-to-end and the final vector is treated as the overall traffic flow.

Let’s look at the members first, and the strong diagonal feature. The blue-green arrows pointing southeast show a strong trend in the morning hours for members to ride in that direction. Recalling the early-morning spike in member traffic, these arrows represent the morning rush hour. The orange-red arrows pointing northwest represent the evening commute. The pattern for members is very strong: the overall traffic flow is dominated by commuters and flows diagonally across the city in two distinct periods.

For casual users the signal is weaker, showing that casual riders tend to ride to more varied destinations. Still, there is a clear distinction shown by the colours: morning traffic trends east and afternoon & evening traffic trends west.

Let’s break this down further and split the trips into weekends vs weekdays.

Things become clearer. During the week, casual traffic follows a similar pattern as members, suggesting that many of these trips are actually for commuting.

Next, let’s examine casual traffic flow only.

We see the commuting pattern during the weekdays, traveling mostly along the northwest-southeast diagonal. On the weekend however, things are more interesting. Many casual trips are taken in the morning to early afternoon, traveling northeast. In the afternoon the traffic flow swings to the west. Recalling our map of casual hot spots earlier, we suggest that a majority of casual users are taking trips to the waterfront, spending some time there, and then returning to their homes in the west.

As one last view, let’s examine how these patterns evolve over a typical week.

Typical traffic volume patterns

All traffic flow

When we look at the overall traffic flow for the city, it is remarkably consistent, day to day and between members and casuals. Traffic flows in to the waterfront from all directions, and flows out from the waterfront either to the northwest or southwest, depending which side of Navy Pier one is on.

Traffic flow patterns: showing all bike stations